A conventional mechanism for converting both forward and reverse movements of a reciprocating member into a rotary motion in one direction is disclosed in Japanese Laid-Open Patent Publications Nos. 52-154964 and 58-61353.
In the conventional mechanism, pinions are engaged with racks formed on both sides of a rack member which performs reciprocating rectilinear motions, and rotary motions of the pinions are transmitted to an output shaft through respective one-way clutches, and the output shaft is rotated in one direction.
In general, such tools which develop a one-way rotation, like a ratchet type socket wrench, performs reciprocating pivotal motions by grasping a grip by hand to input reciprocating circular arcuate motions.
In the above-mentioned conventional mechanism, however, it is impossible to directly convert a reciprocating circular arcuate motion into a one-way rotary motion, and accordingly, the mechanism as it is can not be applied to tools such as ratchet type socket wrenches.
Further, in the reciprocating rectilinear motion of a rack member, the distances of forward and reverse movements are restricted and are required to be equal in principle. Thus, the conventional mechanism is not adaptable for input members of which the distance of forward or reverse movement is extremely long, or the distance of forward and reverse movements are not equal.